The present invention is generally directed to irrigation sprinklers. More particularly, the invention relates to closed-case impact sprinkler heads with fitted fluid seal assemblies.
Many regions of the world today use irrigation systems for artificial distribution of water. One of the most widely used irrigation systems, particularly where water is not abundant or plentiful, is a sprinkler system wherein one or more sprinkler units are positioned about a land area for distributing water over the surface of the land area. Such systems are widely used in most developed countries for a variety of applications including the irrigation of lawns, golf courses, playing fields and field crops.
Impact sprinklers are generally well known in the art and have been used for many years. There are essentially two broad varieties or types of impact sprinklers. The first type is the open or common riser mounted sprinkler unit which is attached to the end of a riser stem or pipe formed with a water conduit. This type of sprinkler is most often used in open areas such as flower beds or the like which do not require close trimming. These units extend upwardly from the surface and are somewhat obtrusive and unattractive. Consequently, they are used in areas where the units are not readily observed nor require maintenance with lawnmowers. The second type of impact sprinkler is a similar type of unit mounted within a housing which is, in turn, buried beneath the surface of the ground so that the sprinkler generally provides a pop-up unit. These impact sprinklers are most often used in lawn settings, and are mounted within housings or wells that are buried underground. The top of the housings are substantially flush with the ground surface so that open areas such as lawns may be easily landscaped or mowed. When water is supplied to the sprinklers, they pop-up or rise above their housings and the ground surface. In this fashion, the sprinklers remain out of sight until activated. However, the housings for this type of sprinkler, which are designed with an open-case to accommodate standard rotating impact sprinkler arms, tend to become filled with debris such as dirt, grass clippings and the like. Any of the above hamper the ability of the sprinkler to pop-up and to retract, or to effectively drive the sprinkler.
Another common type of irrigation device is known in the art as a gear driven sprinkler. Gear-driven sprinklers have rotating nozzles effectively driven by various gear driving mechanisms which are activated by water supplied to the sprinkler. These sprinklers provide an advantage in that their housings are enclosed by design thus avoiding the problems associated with the open or well-type design of an impact sprinkler. However, it has been observed that gear-driven sprinklers are frequently subject to failure due to debris becoming engaged or lodged within the gear drive mechanism. Many designs are also plagued with a relatively limited watering range due in part to the general power-draining design of the gear driving mechanisms.
The sprinkler literature includes numerous patents relating to variations of sprinkler units known in the art. The following description identifies certain issued U.S. patents, the specifications for all of which are incorporated by reference in their entirety as if stated herein: U.S. Pat. No. 3,602,431 entitled A SPRINKLER DEVICE FOR FLUID DISTRIBUTION (Lockwood) is directed to a sprinkler for distributing water comprising a body, a sprinkler head rotatably connected to the body, a fluid flow interrupter for providing controlled bursts of fluid in the stream of fluid exiting from the sprinkler head, an interrupter drive, a drive means including a free rotating ball for driving the sprinkler head, and reversing means for reversing the direction of movement of the sprinkler head. U.S. Pat. No. 3,765,608 entitled AUTOMATIC INTERMITTENT BREAK-UP DEVICE (Lockwood) is directed to a sprinkler with an automatic intermittent break-up device repeatedly movable toward the center of the fluid stream exiting a nozzle to a first position to increase the break-up of the stream and movable away from the center of the fluid stream exiting the nozzle to a second position to decrease the break-up to provide more desired distribution of fluid on the surface area. U.S. Pat. No. 3,930,617 entitled IMPACT SPRINKLER (Dunmire) is directed to an impact sprinkler which uses a plastic water deflector having a number of cooperating water deflecting surfaces which improve the overall water distribution pattern of the sprinkler; the particular configuration provided for allowing the water deflector to pivot back and forth. U.S. Pat. No. 4,055,304 entitled AUXILIARY BRAKING MEANS FOR IMPACT ARM SPRINKLERS (Munson) is directed to an impact type rotary sprinkler including a rotatable body and nozzle, an impact arm which oscillates responsive to the kinetic energy of the fluid discharge stream and a primary spring which stores the rotational energy of the oscillating arm rotating to impact against the housing and impart an increment of rotation thereto. U.S. Pat. No. 4,103,828 entitled ROTARY SPRINKLER IMPACT ARM SPRING ADJUSTMENT (Ridgway) is directed to a rotary sprinkler with structure for adjusting the force applied to the impact arm by the impact arm spring, viz. a laterally directed nozzle cooperating with the arm to rotate the nozzle and an impact arm on a shaft extending above the nozzle. The arm is mounted within a cage extending above the nozzle. U.S. Pat. No. 4,164,324 entitled SPRINKLER HEAD WITH IMPROVED INTEGRAL IMPACT ARM AND ANTI-BACKSPLASH DRIVE SPOON (Bruninga) is directed to a part-circle rotary sprinkler head having an improved anti-backsplash drive spoon integrally formed as a part of the impact arm. U.S. Pat. No. 4,182,494 entitled ANTI SIDE SPLASH DRIVE ARM FOR AN IMPACT DRIVE SPRINKLER (Wichman) is directed to an impact sprinkler of the full or part circle type with an anti side splash drive arm. Despite these and other known sprinkler designs, there is a need for an irrigation sprinkler that incorporates the advantages provided by both impact and gear-driven sprinkler designs.
The invention provides closed-case impact sprinkler units. The particular features of the described embodiments in the following specification may be considered individually or in combination with other variations and aspects of the invention.
It is an object of the present invention to provide impact sprinkler assemblies with a closed-case design. A sprinkler unit formed in accordance with the invention may include an inner housing and an outer housing which are slidably mounted relative to each other. The unit may have a central shaft slidably mounted within the inner housing, and the upper end of the central shaft may include an outlet nozzle mounted in a turret. The sprinkler units provided herein also have filters for filtering water flowing through the units, and may have an inner valve means in a main through-passage for impeding the flow of water through the sprinkler unit until they are placed in a pop-up position or when the impact arm is clear of the outer body housing. Rotation of the sprinkler is accomplished by the water impact force of the sprinkler arm against and relative to turret and inner housing of the sprinkler. Upon retraction, the inner valve means stops the flow of water thereby allowing the arm to move back into the turret before the inner housing lowers back into the outer housing. The sprinkler units provided herein enable uniform speed of rotation of the turret with different nozzles and flow rates, and provide relatively easy installation and removal for service.
Another embodiment of the invention includes a sprinkler unit with delayed activation. The unit may have an outer case formed with a fluid inlet that is in fluid communication with an interior region of the outer case. A rotatable closed-case turret assembly may be formed with a fluid outlet that is in communication with a central shaft having a lower end shaft portion extending into the interior region of the outer case. An extendable riser sleeve supporting the rotatable turret assembly may be slidably positioned within at least a portion of the interior region of the outer case. The riser sleeve includes a filter with at least one spring retainer extending through a slot formed along a sidewall portion of the riser sleeve, and a valve seat formed along a top portion of the filter that may selectively disengage from the lower end shaft portion of the central shaft to permit the flow of fluid from the interior region of the case into the central shaft. A delayed riser spring assembly may be further included having a first riser spring positioned between the spring retainer and a lower end portion of the riser sleeve, and a second riser spring positioned between the spring retainer and the upper end portion of the outer case. The first riser spring may be compressed when a fluid enters the interior region of the outer casing to move the riser sleeve in a relatively upward direction. The second riser spring may be compressed upon compression of the first riser spring to disengage the valve seat from the lower end shaft portion of the central shaft to permit the flow of fluid from within the interior region of the outer casing out through the fluid outlet. Additionally, the closed-case turret assembly may include an impact sprinkler assembly having an extendable impact arm. The impact arm, turret assembly and riser sleeve may combine to form a substantially continuous cylinder positioned within the interior region of the outer case.
It is a further object of the invention to provide a closed-case impact sprinkler unit. An outer case may house a riser sleeve within the interior region of the outer case that is upwardly extendable from the outer case into a pop-up position. The riser sleeve may be formed with an external surface that is complimentary to the internal surface of the outer case to prevent the introduction of debris into the interior region of the outer case when the riser sleeve is in a pop-up position. In addition, a closed-case turret assembly may be rotatably positioned on the top end portion of the riser sleeve. The turret assembly may include a fluid outlet passageway in communication with the fluid inlet, and a hinged impact arm mounted within the turret assembly that interacts with water ejected from the fluid outlet passageway. Another variation of the sprinkler unit may include a hinged impact arm extendable beyond the turret assembly into an open position when impacted by a fluid that is ejected from the fluid outlet passageway. The unit may further include means for selectively permitting the flow of fluid into the fluid outlet passageway to extend the impact arm into an open position only when the riser sleeve is placed in a pop-up position.
A dual-stage sprinkler head is further provided in accordance with the concepts of the invention. The sprinkler head may include an outer sleeve having an interior chamber and a fluid inlet, and an inner sleeve having a fluid outlet that is slidably positioned in at least a portion of the interior chamber of the outer sleeve. The inner sleeve may include a slidably connected spring retainer connected to a valve assembly that selectively permits the passage of a fluid from the fluid inlet to the fluid outlet when moved relatively downward with respect to the inner sleeve. In addition, the sprinkler head may include a riser spring assembly having a first spring positioned between the spring retainer and a lower end portion of the inner sleeve, and a second spring positioned between the spring retainer and an upper end portion of the outer sleeve. The first spring may be compressed during a first stage as the inner sleeve rises when fluid enters from the fluid inlet into the interior chamber of the outer sleeve, and the second spring may be compressed during a second stage as the first spring moves towards a compressed state to move the spring retainer relatively downward with respect to the inner sleeve to permit the passage of fluid through the sprinkler unit. In addition, a turret may be rotatably mounted the top portion of the inner sleeve, and an impact arm may be rotatably mounted to the turret. The impact arm may selectively extend to an open position only during the second stage when the valve assembly permits the passage of fluid to the fluid outlet. Furthermore, the impact arm may be rotatably mounted to the turret with an off-centered hinge pin. An nozzle may direct fluid towards the impact arm wherein the nozzle includes a fluid vane positioned within its interior region to direct fluid flow out of the nozzle.
Another aspect of the invention provides an impact sprinkler head with extended sprinkling range. The sprinkler head may include an outer sleeve formed with an end opening and an internal surface having a fixed trip, and a trip collar rotatably mounted to the end opening of the outer sleeve, wherein the trip collar includes an adjustable trip. An impact sprinkler head and turret assembly may be rotatably connected to the trip collar having a trip assembly for reversing direction of the impact sprinkler head and turret assembly. The trip assembly may further include an elongated actuator opening, and a trip pin pivotally mounted within the actuator opening to provide lateral movement of the trip pin within the actuator opening to initiate a delayed reversal of the trip assembly upon contact with either the fixed or adjustable trip to provide an extended sprinkling range. It is a further object of the invention to provide a reversible drive sprinkler unit with a rotary drive that is a significant improvement over the well-known impact arm concept, and can drive the sprinkler through a desired arc of coverage. The sprinkler arc may be a full circle or a reversible partial circle with the arc of coverage being adjustable with control mechanisms provided herein.
With respect to yet another aspect of the invention, closed-case sprinkler units are provided herein with fitted fluid seal assemblies. Various fluid seal assemblies described herein may reduce the entry of grit and dirt into the waterstream within the unit. An embodiment of the invention provides a dirt resistant bearing system for a sprinkler unit with a rotatable turret having a central shaft extending into a support channel formed within an inner housing. The central shaft may be formed with a relatively upper shaft portion and a relatively lower shaft portion, and the support channel may be formed with an upper channel region and a lower channel region. A first bearing and sealing assembly may be fitted substantially around an outer perimeter of the upper shaft portion and in communication with the upper channel region, and a second bearing and sealing assembly may be fitted substantially around an outer perimeter of the lower shaft portion and in communication with the lower channel region. These bearing and sealing assemblies may include various combinations of sealing and bearing washers that promote a fluid seal between movable components within the sprinkler unit such as a support channel and a central turret shaft. The outer and inner diameter regions of the assemblies may be thus sealed under a water and/or spring load while supporting the rotatable turret shaft.
In yet another aspect of the invention, a sprinkler head is provided with a fitted serrated seal assembly. The fitted seal assembly may include an outer case having an interior region, and a pop-up sprinkler head turret mounted on a riser sleeve slidably mounted within the interior region of the outer case. The turret may be formed with an elongated central shaft for the passage of water. A water filter may be positioned within the riser sleeve having a valve stem for communication with a lower end portion of the central shaft. The communicating surfaces of the lower end portion of the central shaft and the valve stem of the water filter may be formed with complementary serrated surfaces. Additionally, the lower end portion of the shaft may be defined by or include a removable inlet nut with matching serrations within the inner perimeter of the nut portion for contact with a complementary surface surrounding an exterior portion of the water filter valve stem.
Other objects and advantages of the invention will become apparent upon further consideration of the specification and drawings. While the following description may contain many specific details describing particular embodiments of the invention, this should not be construed as limitations to the scope of the invention, but rather as an exemplification of preferable embodiments. For each aspect of the invention, many variations are possible as suggested herein that are known to those of ordinary skill in the art.